Skid support construction



Nov. 30, 1965 D. LOTT 3,220,712

SKID SUPPORT CONSTRUCTION Filed Aug. 29. 1961 INVENTOR.

JACK D. LOTT United States Patent SKID SUPPURT CONSTRUCTIUN Jack D. Lott, 524 East 1st South, Provo, Utah Fiied Aug. 29, 1961, Ser. No. 134,686 3 Claims. (Ci. 2636) This invention relates to continuous reheating furnaces for metal slabs and the like, and more particularly to a skid support construction for such furnaces.

Iron slabs, steel ingots, billets and the like are propelled through reheat furnaces over elongated skids, usually arranged in pairs, and supported at appropriate intervals on cross beams. The beams in turn rest on posts that extend up from the floor of the furnace. The skids, beams and posts are made of thick-walled pipe through which water passes to cool the members to a temperature consistent with preservation of their structural strength and rigidity.

In order that each skid may expand and contact logitudinally with changes in furnace temperature without moving laterally along the beams, a saddle or spacer block is fixed to each beam at the skid crossover point and serves to support and cradle the skid. These saddles fail frequently because of continuous and full exposure to the intense heat of the closely spaced slabs which softens and/or disintegrates the saddle structure. Frequent replacement of saddles is time consuming, tedious and costly in terms of furnace shutdown.

In accordance with this invention, excessive heating of the saddle is avoided by a combination of efficient cooling and of heat shielding of the affected parts. Maximum heat transfer from these solid saddle parts to the coolant in the pipes is afforded by providing substantial area contact of skid and beam to the saddle.

A general object of this invention is the provision of a durable saddle construction for supporting skids on cross beams in reheat furnaces.

A further object is the provision of a saddle which is effectively shielded from the heat emanating from slabs being processed.

Another object is the provision of a saddle construction from which heat is rapidly transferred to the coolant in adjacent supporting pipes.

These and other objects of the invention will become apparent from the following description of a preferred embodiment thereof, reference being had to the accompanying drawing in which:

FIGURE 1 is a perspective view of a portion of skids and cross beams in a preheating furnace;

FIGURE 2 is an enlarged transverse section taken on line 2-2 of FIGURE 1, showing the saddle construction embodying my invention;

FIGURE 3 is a section taken on line 33 of FIGURE FIGURE 4 is a plain view of the skid and cross beam shown in FIGURE 2; and

FIGURE 5 is a transverse section of a modified form of skid.

Referring now to the drawing, FIGURE 1 shows an arrangement of supports over which slabs and the like are moved through a reheat furnace. These supports comprise elongated skids 10, usually arranged in pairs and extending from the entrance to discharge ends of the furnace. The slabs to be heated, one of which is indicated in broken line designated S, move in the direction of the arrow over the skids. Cross beams 12 extend transversely of the direction of slab movement and under the skids to support the latter at appropriate longitudinally spaced points. These cross beams are secured to the upper ends of vertical posts 14 which extend up from the floor of the furnace. Skids 10 are "ice spaced from the beam at their crossover points by saddles 15 described in detail below. Posts 14, beams 12 and skids 10 are made up of heavy walled pipe through which water or other coolant is pumped as part of a cooling system, not shown.

Each saddle 15 comprises a tongue block18, see FIG- URES 2, 3 and 4, having a rectangular cross-section and secured directly under and to skid It), and a groove block 19 of similar cross-sectional shape fixed to the uppermost part of the cross beam 12 and formed with an upwardly opening channel-like groove extending transversely of and in the center of block 19 and into which tongue block 18' loosely fits. The width W of block 18 preferably is slightly narrower than the corresponding dimension of groove 20 and the length L of block 18 is substantially greater than the width W of block 19 to permit freedom of movement of the skid in the direction of its length while restraining movement in other directions. Block 18 also'has a width substantially less than the diameter D of skid 10 and is located symmetrically of the vertical plane containing .the axis of the skid so that the latter essentially shieldsblock 18' from heat directed down fromslab' S.

The depth G of groove'20 is about the same as or slightly less than the radial thickness T of block 18' so that the uppermost parts of groove block 19 are spaced from the heated slab at least by the diameter of skid 12.

Blocks 18 and 19 are firmly bonded to skid 10 and cross beam 12, respectively, as by welding, and thus are in good heat conducting relation with the coolant in these members. Block 19 preferably is longer along its base 19a than its upper extremity 19b to enhance this heat transfer. Block 19 has a width W substantially less than the diameter of D of beam 12 and is located substantially symmetrically of the vertical plane containing the axis of the beam which therefore shields this block from hot furnace gases directed toward the underside of the slab S.

The above described construction of the saddles preserves their strength and rigidity in the intense heat of the furnace and under the heavy load of slabs processed therein. The lowermost part of the tongue block 18 that is bottomed in groove 20 is effectively shielded from radiant heat from any direction within the furnace. The top 19b of groove block 19 is spaced from slab S at least by a distance equal to the diameter D of the skid, and the latter further partially shields this extremity of block 19. Long life of these solid structural members is thus enhanced and uninterrupted furnace operation for more extended periods is realized.

In order to minimize the cooling effect of skid 10 on slab S, a small diameter slab support bar 24, see FIG- URE 5, may be secured to the top of the skid.

Changes in the above described embodiment of my invention may be made by those skilled in the art without departing from the spirit and scope of the invention. It is intended that the appended claims shall define the essentially novel features of the invention.

What is claimed is:

1. In a continuous reheating furnace having hollow elongated slab-supporting skids and hollow cross beams traversing the undersides of said skids, a construction for supporting each skid on a cross beam comprising a first solid block secured to and projecting from the underside of said skid symmetrically of the vertical plane containing the axis of the skid, said first block having a width substantially less than the diameter of the skid whereby the latter shields the block from heat directed downwardly from the slab, a second solid block secured to and projecting upwardly from said beam symmetrically of the vertical plane containing the axis first block from said skid whereby the upper part of 10 the second block is below the skid, the lower part of said second block being longer than the upper part thereof whereby a maximum heat conducting area is established between said beam and the second block.

2. In a continuous reheating furnace having hollow elongated slab-supporting skids and hollow cross beams traversing the undersides of said skids, a construction for supporting each skid on a cross beam comprising a first solid block secured to and projecting from the underside of said skid symmetrically of the vertical plane containing the axis of the skid, said block having a width substantially less than the diameter of the skid whereby the latter shields the block from heat directed downwardly from the slab, a second solid block secured to and projecting upwardly from said beam symmetrical- 25 ly of the vertical plane containing the axis of said beam, said second block having a width substantially less than the diameter of the beam and having an upwardly opening channel-like central transverse groove adapted to receive said first block, the width of said groove being greater than the width of said first block whereby the latter is free to move relative to the second block in a direction parallel to the skid axis but is constrained against movement in other directons, the depth of said groove being less than the projection of said first block from said skid whereby the upper part of the second block is below the skid.

3. In a continuous reheating furnace having an elongated skid and a transverse cross beam, saddle means to support said skid on said beam comprising a tongue block secured to and projecting downwardly from the underside of said skid, and a groove block secured to and projecting up from the upper side of said beam, said groove block having an upwardly opening groove for receiving said tongue block and constraining lateral movement of the skid along the beam.

References Cited by the Examiner UNITED STATES PATENTS 1,788,796 1/1931 Issacs et al 2636 2,105,838 1/1938 McCormick 263-6 FOREIGN PATENTS 979,712 11/1954 Germany.

WHIT MORE A. WILTZ, Primary Examiner. RAY K. WINDHAM, Examiner. 

1. IN A CONTINUOUS REHEATING FURNACE HAVING HOLLOW ELONGATED SLAB-SUPPORTING SKIDS AND HOLLOW CROSS BEAMS TRAVERSING THE UNDERSIDES OF SAID SKIDS, A CONSTRUCTION FOR SUPPORTING EACH SKID ON A CROSS BEAM COMPRISING A FIRST SOLID BLOCK SECURED TO AND PROJECTING FROM THE UNDERSIDE OF SAID SKID SYMMETRICALLY OF THE VERTICAL PLANE CONTAINING THE AXIS OF THE SKID, SAID FIRST BLOCK HAVING A WIDTH SUBSTANTIALLY LESS THAN THE DIAMETER OF THE SKID WHEREBY THE LATTER SHIELDS THE BLOCK FROM HEAT DIRECTED DOWNWARDLY FROM THE SLAB, A SECOND SOLID BLOCK SECURED TO AND PROJECTING UPWARDLY FROM SAID BEAM SYMMETRICALLY OF THE VERTICAL PLANE CONTAINING THE AXIS OF SAID BEAM, SAID SECOND BLOCK HAVING A WIDTH SUBSTANTIALLY LESS THAN THE DIAMETER OF THE BEAM AND HAVING AN UPWARDLY OPENING CHANNEL-LIKE CENTRAL TRANSVERSE GROOVE ADAPTED TO RECEIVE SAID FIRST BLOCK, THE WIDTTH OF SAID GROOVE BEING GREATER THAN THE WIDTH OF SAID FIRST BLOCK WHEREBY THE LATTER IS FREE TO MOVE RELATIVE TO THE SECOND BLOCK IN A DIRECTION PARALLEL TO THE SKID AXIS BUT IS CONSTRAINED AGAINST MOVEMENT IN OTHER DIRECTIONS, THE DEPTH OF SAID GROOVE BEING LESS THAN THE PROJECTION OF SAID FIRST BLOCK FROM SAID SKID WHEREBY THE UPPER PART OF THE SECOND BLOCK IS BELOW THE SKID, THE LOWER PART OF SAID SECOND BLOCK BEING LONGER THAN THE UPPER PART THEREOF WHEREBY A MAXIMUM HEAT CONDUCTING AREA IS ESTABLISHED BETWEEN SAID BEAM AND THE SECOND BLOCK. 